Problem: Simplify the following expression: $p = \dfrac{2x}{2} + \dfrac{-4x}{2}$
Since the expressions have the same denominator we simply combine the numerators: $p = \dfrac{2x - 4x}{2}$ Combine like terms: $p = \dfrac{-2x}{2}$ Simplify by dividing numerator and denominator by 2: $p = \dfrac{-x}{1}$ $p = -x$